1. Technical Field
This invention relates to integrated circuits and, more particularly, to a microwave monolithic downconverter integrated circuit.
2. Discussion
Gallium arsenide (GaAs) circuits have greatly improved the performance of microwave electronic devices. However, most GaAs microwave devices in use are discrete devices such as transistors, since many of the technical problems involved with incorporating more complex circuitry of this type on single monolithic chips have not been overcome. As a result, microwave integrated circuits in general are hybrid devices comprising a combination of discrete devices and monolithic devices assembled on a single substrate. Unfortunately, such hybrids are more costly, bulky and power hungry than monolithic integrated circuits would be.
Further advances in GaAs technology have resulted in high electron mobility transistors (HEMT) which further improve the performance of microwave devices. However, the use of HEMT transistors in hybrid circuits still result in the aforementioned disadvantages inherent in the hybrid technology.
Thus, it would be desirable to provide a monolithic microwave integrated circuit to avoid the disadvantages of hybrid processes. Further it would be desirable to provide such a circuit which takes full advantage of the HEMT GaAs technology. Also, it would be desirable to provide a monolithic microwave integrated circuit which is less costly, bulky and power hungry than conventional hybrid microwave integrated circuits.